细晶粒陶瓷的制备及性能研究

采用溶胶-凝胶法制备出Pb0.93La0.07（Zr0.57Ti0.43_0.9825O3的纳米粉体，并用其烧结陶瓷，制备出细晶粒PLZT陶瓷．讨论纳米粉体粒径的大小、物相的形成条件及其对细晶粒PLZT陶瓷的微观结构和压电介电性能的影响．结果表明，随着纳米粉体尺寸的减小，PLZT陶瓷晶粒尺寸降低，与传统固相法烧结的陶瓷相比，细晶粒PLZT陶瓷的室温介电常数增加，压电性能较高．

Preparation and properties of fine-grained ceramics

Lanthanum-doped lead zirconate titanate Pb1-y Lay （Zrx Ti1-x）O3 （PLZT） is an important piezoelectric ceramic material, which has been applied in various fields. In the present study, PLZT nanocrystal powder had been prepared by sol-gel method. The cold pressed pellets made of PLZT nanopowder were sintered at different temperatures. It indicated that a single phase fine- grained ceramics of PLZT had been formed by roasting at 1 250 ℃ for 2 h, which had smaller grain size and better dielectric piezoelectric properties compared to the traditional solid-phase method. The microstructure, grain size and dielectric piezoelectric properties of PLZT ceramics were found to be sensitive to the particle size of PLZT nanopowder. The dielectric piezoelectric properties of PLZT polarized ceramics could be improved with the lessening of PLZT nanopowder size. Meanwhile, the grain size of PLZT ceramics decreased.